This invention relates to a helmet-liner suspension structure which is selectively installable in the shells of helmets, and in particular, to such a structure which has a universal characteristic that allows it to be quickly, conveniently and fittingly mounted in the shells of helmets that have different sizes within a defined range of sizes. Especially, the invention is designed for use in helmet shells that have a generally common pattern of plural, pre-established and located, spaced attachment sites (referred to as host attachment sites) that have known and predetermined relative locations within the helmet shells that make up the range of sizes mentioned above.
A preferred embodiment of the invention is described herein particularly in the setting of a military helmet shellxe2x80x94a setting wherein the invention has been found to offer particular utility. It should be noted, however, that the invention and its features have utility just as well in other specific and different kinds of helmet shells.
So-called helmet-liner suspension structures play quite large roles in helmet construction and performance, particularly in a field, such as the military field, where closely fitting, position-stable helmets often need to be worn for long, extended time periods. Positional stability, long-term comfort, inherent strength, shock management capability, ease of repair/installation, and if need be quick replacement, of worn or damaged components, and a quality of universality, collectively dominate helmet construction concerns in, for example, the field of the military. Within this field of military helmet shells, all sizes are generally characterized by a common, defined and controlled attachment pattern for securing inside liner suspension structures. Specific relative spacings between attachment sites that have standardized patterns for the different sizes of military helmets are substantially always characterized by a common xe2x80x9clocatingxe2x80x9d attachment host site that is typically located at the rear of a helmet shell. this locating site is usually centered rearwardly on a pattern of plural other attachment sites, typically five other sites, including two such additional sites along either side of a helmet shell, and a central front site.
Within such a family of generally related helmet shells in different sizes, the specific distances that exist between, for example, the lateral side attachment sites for a linear suspension system, and the central rear locating site, differ from helmet-shell size-to-size. Lack of convenient universality and simplicity in relation to matching up suspension structures and helmet shells results in a situation where a specific suspension system needs to be typically prepared and sized for each of the different specific helmet-shell sizes within the range of sizes in such a family of shells. Obviously, this is a fairly expensive proposition, and in circumstances, which often characterize events facing military personnel, inside helmet liner suspensions damaged, and need to be replaced in very quick order, often under difficult field conditions, where speed of assembly and assured fitment of a new liner suspension system in a helmet shell are very important considerations.
Especially important to be taken into account in conjunction with offering any kind of an interior liner suspension system in a helmet shell is that it must perform all of the general utilitarian functions required of such systems, such as the support of contact structure which directly contacts a wearer""s head, attachment of additional gear, such as head sets and other paraphernalia that may be required to be attached to a helmet for hands-free wearing and perhaps use, and of course, long-term comfort for the wearer, under circumstances which do not sacrifice positional stabilityxe2x80x94one of the very important other functional requirements of a liner suspension system. Helmet interior structure is also employed frequently to carry miscellaneous other things, such as maps, notes, letters, etc.
The present invention proposes a helmet liner suspension structure (or system) which substantially meets all objectives, and handily so, that address the various above-expressed important behaviors and characteristics preferably possessed by liner suspension systems. Specifically, the invention distinguishes itself from conventionality, inter alia, by offering universality of fitment and ease thereof, along with clear and quick and simple retrofittably into various already-existing helmet shells having prior art liner suspension systems previously installed. The liner suspension system of the present invention is based upon a careful and sophisticated structural design that maximizes all of the functional qualities expressed above in a single size-adaptive, single-construction suspension unit. It thus truly offers a high-performance internal helmet liner suspension system which can be characterized with the phrase xe2x80x9cone size fits allxe2x80x9d, and with respect to which (a) manufacturing (procedurally) is very simple and quite inexpensive, and (b) installation and surety of proper fitment are easy and confident.
Proposed specifically by the present invention is an elongate unitary band which is formed, as by water-jet cutting or stamping, from an appropriate springy, resilient plastic material such as Dupan Lexan(copyright) polycarbonate with a thickness of about 0.060-inches.
This elongate band, in a developed or flattened form, lies substantially flat in a plane with a gentle elongate curvature displayed from end to end.
To install this band, the band is bent to close and overlap its opposite ends upon themselves to form, generally speaking, the appearance of an endless, curved loop in which the bent band per se forms a slightly angularly flaring, closed ovate form. The flaring quality of the bent band gives it the appearance, when it is in an operative condition in a helmet shell, of a small cross-section of a conical structure whose walls slope at a very slight angle upwardly and inwardly all away around the bent and closed band.
In this band, there are provided plural mounting openings, or apertures, (guest affixing sites) including a central locating circular hole, and plural elongate mounting slots. This hole and these slots are designed to match up with the several mounting locations that are provided in the range of helmet sizes to which the present invention is aimed for fitment. In the helmet shells now being discussed, namely, military helmet shells, the locating holes therein for positioning internal liner suspension structures are always centered at the rear of the shell, and typically five other mounting holes are provided, with four of them being positioned as pairs along the opposite lateral sides of the helmet shell, and with the fifth being provided centrally at the front of the shell.
According to an important feature of the present invention, slots that are provided in the band, on opposite sides, so-to-speak, of a central mounting hole, are positioned and given respective lengths whereby, no matter which helmet shell size is chosen for installation of the invention, these slots will always provide clear access to the installation of mounting hardware that effectively passes through the slots of the invention and into the predetermined and pre-located lateral and front mounting holes provided in a helmet shell.
Integrated with the band of the invention are two pairs of downwardly depending, completely integral, chin-strap mounting elements. These elements have generally a flat planar, or bladelike, configuration, and are constructed in such a way that they offer preferential bending along axes contained within their planes and at locations generally downwardly below the main body of the suspension band. These elements, when holding chin-strap structure, permit appropriate bending and flexing so that the tightening of a chin strap with respect to a particular wearer will result in the chin strap seating very securely and very comfortably to the particular wearer""s anatomy. The two forward ones of these chin-strap attaching elements, when the device of this invention is in place inside a helmet shell, slope generally downwardly and slightly forwardly in an angle which further aids in comfortable and appropriate fitting of components in a typical chin-strap structure.
In one modified form of the invention, the band therein is formed with one or more elongate spring fingers (spring-finger structure) which are designed to press against the inside surface of a helmet shell. Such fingers allow for the convenient placement and storage of documents, such as maps.
These and various other objectives and advantages that are offered and attained by the present invention will become more fully apparent as the description which now follows is read in conjunction with the accompanying drawings.